The answer to our energy problem may turn out to be just a bunch of hot air.
And that’s a good thing.
Colorado has been a leader in renewable energy, especially in wind power but with a growing stake in solar as well.
The problem is that those wind generators you see in so many political ads only run about 30 percent of the time — and that’s mostly at night, after peak power demands. Solar is even less reliable, producing electricity just 22 percent of the time, although it does have the advantage of peaking on hot sunny afternoons when demand for power is highest.
The problem, obviously, is how to convert such environmentally benign but intermittent sources of electricity into reliable 24/7 power that comes on when you flick a switch.
Pumped storage such as Xcel Energy’s Cabin Creek plant, is one answer. Built in the 1960s, the facility was designed to use surplus power at night to pump water uphill through reversible pump/generators. When power is needed, the water goes back down hill to spin electrical generators.
Tuesday, the Associated Press reported that Public Service Enterprise Group Inc., the Newark, New Jersey-based owner of that state’s largest electric utility, plans to spend $20 million to develop devices that compress air to store power. That’s another way to convert electricity produced from wind turbines and solar cells into reliable baseload power.
PSEG announced a joint venture with Michael Nakhamkin, an inventor whose system is used at the only North American power plant, located in Alabama, that currently that stores energy underground in the form of pressurized air. When electricity demand rises, the trapped air is released to turn a power turbine.
“Anything that does commercial-scale energy storage is huge,” said John Gardner, a professor of mechanical engineering at Boise State University, told the AP. “It can completely change the economic prospects of a wind farm.”
PSEG will market and license the technology using patents held by Nakhamkin, who is chief technical officer of the new venture and works in Basking Ridge, New Jersey. The systems can be used to generate from 15 to 450 megawatts of power, Nakhamkin said in an interview yesterday. One megawatt is enough to power about 900 average U.S. homes.
“Technologically, this is not rocket science,” said Arshad Mansoor, a vice president at the Palo Alto, California- based Electric Power Research Institute, a consultant on air- storage projects.
About three quarters of the U.S. has geologic formations that could be used for compressed air storage, Mansoor said. There could be 20 to 50 power plants producing 100 to 300 megawatts each that use the technology by 2020, he said.